This invention generally relates to end pieces to be used in connection with tools for delivering fasteners to a work piece, and more specifically relates to an end piece which can be used with fasteners of different lengths.
The end piece of the present invention can be used with a drive tool for driving fasteners into a workpiece. For example, the end piece of the present invention can be used with either of the drive tools described in U.S. patent application Ser. No. 09/680,761 or U.S. patent application Ser. No. 09/815,809 both of which are incorporated herein in their entirety by reference. The drive tool shown in FIG. 1 relates to U.S. patent application Ser. No. 09/815,809 and is an example of the drive tool in which the end piece of the present invention can be used. The drive tool 10 is configured to allow the operator to install a fasteners into a workpiece while he remains standing. The drive tool 10 includes a central housing 11, a funnel structure 12 located proximate to the central housing 11 and an end piece 14 mounted at the distal end of the central housing 11. When operating the drive tool 10, fasteners are loaded into the funnel structure 12 and are delivered to the end piece 14 one at a time. An aperture 16 is provided at the distal end of the end piece 14. The fasteners are delivered from the end piece 14 to the work piece through the aperture 16. As shown in FIG. 2, the end piece 14 includes a side wall 18, a central passageway 20 defined by the side wall 18 and an aperture 22 through the side wall 18. When the drive tool is in operation, fasteners travel to the end piece 14 through the aperture 22 in the side wall 18, through the central passageway 20 and exit the end piece 14 through the aperture 16 at the distal end of the end piece 14.
Fasteners used in connection with the drive tools will vary in length depending upon the application for which the fastener is used. The end piece must be of an appropriate length to accommodate the fastener to be installed. Each end piece provided with the drive tools of the prior art are designed to accommodate fasteners within a relatively small range of lengths, generally one inch. If the operator desires to install fasteners of a greater or smaller length than the range allowed by the end piece currently mounted to the drive tool, a different end piece must be mounted onto the tool. Thus, in the past, multiple end pieces were provided for each drive tool to accommodate the varying length of fasteners. For example, a drive tool may include a set of three end pieces of varying lengths which can accommodate fasteners of the most common lengths. The end pieces are generally formed from steel and are relatively heavy.
One disadvantage of supplying multiple end pieces with each drive tool is that each additional end piece increases the overall weight of the drive tool and its components. The increased weight makes the drive tool and its components more difficult to transport and increases shipping costs.
Another disadvantage of providing multiple end pieces is that additional material and manufacturing costs are incurred. Not only does the manufacture of each end piece require the supply of additional steel, but each manufacturing step to form the end piece (e.g. machining, drilling etc.) adds to the production cost of each end piece.
During use, the end piece of a drive tool is generally subjected to substantial forces. Still another disadvantage of providing multiple end pieces of different lengths is that if a portion of a particular sized end piece becomes worn or damaged, the entire end piece must be replaced. Until the end piece is replaced, the drive tool cannot be used to drive that respective sized fastener.
An embodiment of the present invention provides an improved end piece which is directed to overcome at least some of the problems presented in the prior art.
A general object of an embodiment of the present invention is to provide an end piece which can accommodate fasteners of varying lengths.
An object of an embodiment of the present invention is to provide an end piece which has a length that can be varied easily.
Yet another object of an embodiment of the present invention is to provide an end piece which eliminates the need to supply multiple end pieces with a given drive tool in order to provide that the drive tool can be used to drive various length fasteners into a work piece.
Still another object of an embodiment the present invention is to provide a single end piece which can accommodate various length fasteners thereby reducing the overall weight of the end pieces which must be supplied with a drive tool.
Still yet another object of the present invention is to provide an end piece which consists of a plurality of replaceable components.
Briefly, and in accordance with at least one of the foregoing objects, an embodiment of the present invention provides an improved end piece for a drive tool which delivers fasteners to a work piece. The end piece includes an upper end piece and a lower end piece. By inserting a spacer between the upper and lower end pieces, the length of the end piece can be adjusted to accommodate fasteners of varying lengths. The spacer can include one or more spacer components to allow for an even greater variety of end piece lengths. Portions of the upper end piece, spacer components and lower end piece are threaded to allow for easy adjustment of the end piece""s length.
By varying the length of the end piece, multiple end pieces are no longer needed to install varying length fasteners. Preferably, the cost of manufacturing one adjustable length end piece is less than the cost of manufacturing multiple end pieces of varying lengths. In addition, preferably the weight of a single adjustable length end piece is less than the weight of multiple end pieces of varying lengths. Finally, the end piece is preferably comprised of a plurality of replaceable components such that if a component becomes damaged or worn, the individual component can be replaced rather than replacing the entire end piece. Additionally, depending on which component has become damaged or worn, the remainder of the end piece components may be useable until the damaged component is replaced.